a knockout mutant for NSH1 shows symptoms of accelerated senescence, accompanied by marked accumulation of uridine and xanthosine under conditions of prolonged darkness.
isoform NSH1 represents the leading activity for both pyrimidine and purine nucleoside hydrolysis. Isoform NSH3 functions as an extracellular, purine-specific hydrolase that is involved in degradation of extracellular nucleosides and may participate in wound and pathogen responses. Isoform NSH2 acts during the late phase of senescence and may support inosine breakdown
possible role of CU-NHs in the breakdown of modified nucleosides derived from RNA molecules